60 



G. sagittarice, Kirby, is a dark brownish species (with the exception of a yellowish 

 line around the margin of the wing-covers), which I have found about the middle of Sep- 

 tember abundant upon the leaves of the water-lily, in the larval, pupal, and perfect 

 stages. It is also given by Packard as occurring upon the willow. 



We now come to a large group consisting of several genera of small — often minute — 

 beetles having the thighs of the hind pair of legs much enlarged and very powerful, by 

 which the beetles are enabled to jump a great distance (in proportion to their size) when 

 disturbed. From this characteristic they are known as Halticas, or Flea-beetles. 



The genus Oedionychis contains a number of species, of which 0. quercata, Fab., is a 

 common one. It is a dark bettle, of oval form and variable markings. Its name as- 

 sociates it with the white oak, and it is found upon other trees as well. 



Another extensive genus is Disonycha which contains some of our handsomest Flea- 

 beetles. D. glabrata, Fab., a pretty little beetle with yellow and black striped wing- 

 covers ; D. collaris, Fab., a bluish-black beetle with a red thorax, and D. triangularis, 

 Say, closely resembling the latter, except that it bears three black dots upon the yellowish 

 thorax, may be found in October sheltering themselves under cornices of buildings, or in 

 ■crevices, etc. They may also be found early in spring under stones, loose bark, etc., where 

 they have hibernated. I). alternata, 111., a large handsome species is rare here. 



Graptodera chalybea, 111., is well known to grape growers as the Grape-vine Flea- 

 beetle. In some seasons it is very abundant, and inflicts a considerable amount of injury. 

 The greatest loss is caused by such beetles as have hibernated under loose bark, fallen 

 leaves, and stones, or in crevices, outbuildings, or other refuges from cold, and which 

 appearing early in April bore into and feed upon the bursting buds. Afterward they 

 feed upon the young leaves, on which during May the female deposits clusters of small 

 orange eggs. Soon hatching, the little dark- 

 coloured larvae (Fig. 72 a), proceed to riddle 

 the leaf, and when very numerous may 

 completely devour it ; b, shows one en- 

 larged, the faint line indicates the natural 

 length. At the end of a month the larva 

 descends from the vine and pupates in a 

 small earthern cell (Fig. 72, c), from which 

 the beetle (d, enlarged) emerges about three 

 weeks later. It then feeds upon the leaves, 

 but does, however, comparatively trifling 

 damage. Such beetles as do not fall a 

 prey to various enemies seek, on the ap- 

 proach of cold weather, a sheltered retreat 

 in which to spend the winter. There is 

 only one brood each summer. The best 

 method of checking their ravages is to 

 collect them (as proposed by Mr. L. 0. 

 Howard, Asst. -Entomologist to Depart- 

 ment Agriculture, Washington) upon sheets 

 drenched with coal oil. 



Phyllotreta vittata, Fab. (Haltica striolata, 111.) the Striped Turnip-flea-beetle is 

 one of our very commonest insects. It may be found at any time during the season, 

 from the first mild days of spring until the end of October. During the earlier months 

 it appears in swarms upon various plants, and upon fences, etc. The larva (Fig. 73, a) 

 is a slender white grub, one-third of an inch long, feeding upon 

 roots underground, where, in a little eartliern cell, it changes to a 

 naked white pupa (6). About a fortnight later it emerges as il 

 little black beetle (also shown in Fig. 73), less than one-tenth of 

 an inch long, but readily determined by the waved, yellowish or 

 reddish stripe on each wing-cover, the stripe sometimes being in- 

 terrupted so as to form two spots. The beetles feed upon the 

 seed-leaves of turnips and cabbages, as well as upon other veget- 



Fig. 73. 



